The field of the invention is home video games and personal computers which receive removable cartridges that contain programs stored on non-volatile memory devices.
Home video games and many personal computers have a connector into which a program cartridge can be inserted. The program cartridge contains a program for operating the video game unit or personal computer and it is typically stored in a non-volatile memory device such as a mask programmable ROM. The program cartridges are mass produced and sold to the end user through retail outlets.
The sales price of program cartridges far exceeds the cost of their manufacture. One of the major reasons for this high price is the cost of developing the program or the cost of purchasing the rights in an existing program. In addition, as with the production of recordings and motion pictures, only a small fraction of the programs which are marketed are highly successful, and the profits on these must offset the losses on the unsuccessful productions.
A number of techniques are available to reduce the price charged to the user for a program. For example, the program cartridges may be rented for a time period as is commonly done with video cassette recordings of motion pictures. When the rental period expires, the user returns the program cartridge to the retailer. Another approach is disclosed in U.S. Pat. No. 4,247,106 in which a receiver of program material is connected to a CATV or MATV cable network. A selected program is "downloaded" to the receiver and stored in a volatile RAM memory which is used to operate the video game unit or personal computer. The user is charged for the use of the program while it is maintained in the receiver.